[MC-96028] No sound in Minecraft 1.8.9 on OS X (fixed by using master from OpenAL)

Minecraft plays without any sound on my system. When I launch the game, I see the following in the "Game Output" tab of the Launcher:

[12:53:05] [Sound Library Loader/INFO]: Starting up SoundSystem...
[12:53:06] [Thread-6/INFO]: Initializing LWJGL OpenAL
[12:53:06] [Thread-6/INFO]: (The LWJGL binding of OpenAL.  For more information, see http://www.lwjgl.org)
AL lib: (EE) ca_open_playback: FindNextComponent failed
[12:53:06] [Thread-6/ERROR]: Error in class 'LibraryLWJGLOpenAL'
[12:53:06] [Thread-6/ERROR]: Unable to initialize OpenAL.  Probable cause: OpenAL not supported.
[12:53:06] [Thread-6/WARN]: ERROR MESSAGE:
[12:53:06] [Thread-6/INFO]: Could not open ALC device
[12:53:06] [Thread-6/WARN]: STACK TRACE:
[12:53:06] [Thread-6/INFO]: org.lwjgl.openal.AL.init(AL.java:162)
[12:53:06] [Thread-6/INFO]: org.lwjgl.openal.AL.create(AL.java:148)
[12:53:06] [Thread-6/INFO]: org.lwjgl.openal.AL.create(AL.java:102)
[12:53:06] [Thread-6/INFO]: org.lwjgl.openal.AL.create(AL.java:201)
[12:53:06] [Thread-6/INFO]: paulscode.sound.libraries.LibraryLWJGLOpenAL.init(LibraryLWJGLOpenAL.java:164)
[12:53:06] [Thread-6/INFO]: paulscode.sound.SoundSystem.CommandNewLibrary(SoundSystem.java:1576)
[12:53:06] [Thread-6/INFO]: paulscode.sound.SoundSystem.CommandQueue(SoundSystem.java:2572)
[12:53:06] [Thread-6/INFO]: paulscode.sound.CommandThread.run(CommandThread.java:121)
[12:53:06] [Sound Library Loader/WARN]: ERROR MESSAGE:
[12:53:06] [Sound Library Loader/INFO]: Could not open ALC device
[12:53:06] [Sound Library Loader/INFO]: Starting up SoundSystem...
[12:53:06] [Thread-8/INFO]: Switching to No Sound
[12:53:06] [Thread-8/INFO]: (Silent Mode)

Here's the entire content of the "Game Output" log window, in case it's helpful:

Java HotSpot(TM) 64-Bit Server VM warning: Using incremental CMS is deprecated and will likely be removed in a future release
Completely ignored arguments: [--nativeLauncherVersion, 285]
[12:53:04] [Client thread/INFO]: Setting user: jcarreiro
[12:53:04] [Client thread/INFO]: (Session ID is token:feab21f031ee405eb02485f8cfa935ab:dbf954823ea84b0ca7d7fb17e8a5b500)
[12:53:05] [Client thread/INFO]: LWJGL Version: 2.9.2
[12:53:05] [Client thread/INFO]: Reloading ResourceManager: Default, faithful32pack.zip, CodeCrafted Custom.zip
[12:53:05] [Sound Library Loader/INFO]: Starting up SoundSystem...
[12:53:06] [Thread-6/INFO]: Initializing LWJGL OpenAL
[12:53:06] [Thread-6/INFO]: (The LWJGL binding of OpenAL.  For more information, see http://www.lwjgl.org)
AL lib: (EE) ca_open_playback: FindNextComponent failed
[12:53:06] [Thread-6/ERROR]: Error in class 'LibraryLWJGLOpenAL'
[12:53:06] [Thread-6/ERROR]: Unable to initialize OpenAL.  Probable cause: OpenAL not supported.
[12:53:06] [Thread-6/WARN]: ERROR MESSAGE:
[12:53:06] [Thread-6/INFO]: Could not open ALC device
[12:53:06] [Thread-6/WARN]: STACK TRACE:
[12:53:06] [Thread-6/INFO]: org.lwjgl.openal.AL.init(AL.java:162)
[12:53:06] [Thread-6/INFO]: org.lwjgl.openal.AL.create(AL.java:148)
[12:53:06] [Thread-6/INFO]: org.lwjgl.openal.AL.create(AL.java:102)
[12:53:06] [Thread-6/INFO]: org.lwjgl.openal.AL.create(AL.java:201)
[12:53:06] [Thread-6/INFO]: paulscode.sound.libraries.LibraryLWJGLOpenAL.init(LibraryLWJGLOpenAL.java:164)
[12:53:06] [Thread-6/INFO]: paulscode.sound.SoundSystem.CommandNewLibrary(SoundSystem.java:1576)
[12:53:06] [Thread-6/INFO]: paulscode.sound.SoundSystem.CommandQueue(SoundSystem.java:2572)
[12:53:06] [Thread-6/INFO]: paulscode.sound.CommandThread.run(CommandThread.java:121)
[12:53:06] [Sound Library Loader/WARN]: ERROR MESSAGE:
[12:53:06] [Sound Library Loader/INFO]: Could not open ALC device
[12:53:06] [Sound Library Loader/INFO]: Starting up SoundSystem...
[12:53:06] [Thread-8/INFO]: Switching to No Sound
[12:53:06] [Thread-8/INFO]: (Silent Mode)
[12:53:07] [Sound Library Loader/INFO]: Sound engine started
[12:53:07] [Client thread/INFO]: Created: 1024x1024 textures-atlas

I was able to work around this problem locally by building libopenal.dylib from source (using the current master from https://github.com/kcat/openal-soft) and then updating the contents of ~/Library/Application Support/minecraft/libraries/org/lwjgl/lwjgl/lwjgl-platform/2.9.2-nightly-20140822/lwjgl-platform-2.9.2-nightly-20140822-natives-osx.jar with the new library; after doing this, sound works normally (but note that this work around also requires defeating the update check that would overwrite a modified local copy lwjgl-platform-2.9.2-nightly-20140822-natives-osx.jar with a fresh copy from the server).

I'm happy to help debug the issue further, if needed.